Did you ever find a solution to this? I am seeing the same thing on my Samsung 2032MW.
This is a strange problem indeed.
I was just setting the resolution of my monitor, which I also use as a TV for my Xbox 360, my PS2 and standard Television and the image cuts out.
It plays sound while you're on the channel and the TV's interface still displays properly. Yet the only way I can see what I'm doing is if i put the monitor in PIP mode and have a little box in the bottom right of my screen showing a TV channel.
Whenever I turn PIP off the picture just disappears completely.
I've tried turning it off, unplugging it, plugging it back in and turning it on. This had no effect
Is there a way to reset the monitor? I'm sure that would fix the problem, any other fixes I'd be very grateful.
My monitor model is a Saumsung SyncMaster2032MW
Cheers

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